The following discussion is an archived debate of the proposed deletion of the article below. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review). No further edits should be made to this page.

The result was keep. Spartaz ^Humbug! 16:01, 30 November 2018 (UTC)[reply]

MacCullagh ellipsoid[edit]

MacCullagh ellipsoid (edit | talk | history | protect | delete | links | watch | logs | views) – (View log · Stats)

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The given definition is exactly that of Poinsot's ellipsoid. The name of "MacCullagh ellipsoid" is highly uncommon, as a Scholar Google search on it gives only three references in English (and two in German). This article is entirely based on a primary source, the original MacCullagh's paper of 1849. D.Lazard (talk) 12:32, 19 November 2018 (UTC)[reply]

I am quite sorry to tell all that D.Lazard's claim that "MacCullagh ellipsoid the eaxctly Poinsot's ellipsoid is an utter display of ignorance. He was impatient to display it although he was already answered at the ellipsoid talk page. I also provided an additional source discussing the difference in Zhuravlev Foundations of Theoretical Mechanics (Fizmatlit, Moscow, 2008)) [in Russian]. I pledge to all administrators to preclude D.Lazard from further harassing other editors. Just take look at his shameful record. Cocorrector (talk) 13:01, 19 November 2018 (UTC)[reply]

• Keep The Poinsot Ellipsoid and the MacCullagh ellipsoid are different constructions for modelling the same thing, however the differences in the construction make them useful for differing things - see the following references: 1 2 3 4. I have to admit that my initial position, based on my background in physics, was to redirect/merge, however it seems to be not as simple as I thought. Finally - a reminder to Cocorrector that we are all colleagues here and that we should remain civil in our communications. FOARP (talk) 13:42, 19 November 2018 (UTC)[reply]

Note: This discussion has been included in the list of Mathematics-related deletion discussions. D.Lazard (talk) 17:10, 19 November 2018 (UTC)[reply]

Note: This discussion has been mentioned at WT:WikiProject Physics. D.Lazard (talk) 17:28, 19 November 2018 (UTC)[reply]

• Keep To quote MacCullagh's obituary,

In his first course of lectures (on the Rotation of a solid Body round a fixed Point), he completely solved the case of a body abandoned to its own motions, on receiving a primitive impulse in any direction, under the action of no accelerating forces. This problem he had finished several years before, and was preparing it for publication, when he was anticipated by Poinsot, who published a very elegant tract on the subject. Both theories are founded on the same principles, and exhibit the effects of the forces in different positions of the body, as well as the actual motions of the body itself, by means of an ellipsoid described round the fixed point as a centre. But they differ in employing, not the same but reciprocal ellipsoids, which, though seemingly unimportant, makes this difference, that Mac Cullagh's method, although not superior in clearness or elegance, had the prodigious advantage of enabling him to throw his geometry into the analytical form, and to deduce, from the simplest geometrical considerations, the elliptic integrals which expressed the circumstances of the motion, such as the times of oscillation, revolution, &c. This method also enabled him to find several interesting properties, which Poinsot's mode of treating the question did not so readily exhibit, and which Poinsot had in fact omitted to notice.

Overall, where there might be an argument for a merge-and-redirect, that can be decided at a later date. There's a whole lot of lovely nineteenth-century classical dynamics here, and a deletion discussion is probably not the best forum for deciding how to present it well. XOR'easter (talk) 18:51, 19 November 2018 (UTC)[reply]

Note: This discussion has been included in the list of Science-related deletion discussions. XOR'easter (talk) 18:53, 19 November 2018 (UTC)[reply]

• Keep Not really my cup of suspended colloid, but based on the material presented above there are sufficient arguments for keeping this as a separate article. At the very least the concepts are different; whether a merge would be suitable is a different discusson. --Elmidae (talk · contribs) 17:40, 27 November 2018 (UTC)[reply]

The above discussion is preserved as an archive of the debate. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review). No further edits should be made to this page.